The invention relates to an electric switching device with an ultra-fast actuating mechanism for opening electric contacts. The mechanism comprises an electro-dynamic trip unit having a propulsion coil associated with a conducting disk. A stationary contact collaborates in the closed position with a movable contact, said electric contacts being moved to the open position by propulsion of the conducting disk when the propulsion coil is supplied with power. A biasing device is designed to generate a closing force to keep said electric contacts in the closed position. Latching means of the movable contact in the open position comprise a magnetic yoke having an attraction coil designed to provide an attraction force of a movable magnetic armature. Said armature is designed to be driven in movement by the movable contact so as to come into contact with the fixed magnetic yoke.
The invention also relates to a hybrid current interruption switch comprising mechanical opening means and electric opening means in parallel.